double acting oscillating cylinder engine

Hi All,

Last year I made the simple muncaster oscillator, which I enjoyed very much.

This my latest engine the muncaster d/a oscillator.

I seem to have been working on this for ages but with the recent pee awful weather I found myself spending more time in workshop and finally got it running. Only on air and it's a very loose fit, no piston ring, no seals in end caps or stuffing box and with the port face still to be lapped up to the valve block, it's a little "hissy".

Scaled up a little from original so 1/16" = 2mm which makes handling and machining a little easier.

It's been good fun and about 85% there. Would like to oak clad the cylinder and of course paint to finish. Hope it's of interest Geoff

That has turned out nicely, look forward to a little video when it's all painted and tarted up.

That is indeed looking good.

I haven't got a double acting oscillator, neither have I got my next project lined up. This engine could well be my answer to both requirements. May I ask where you got the drawings from?

Jim

Hi Jason/Jim

That has turned out nicely, look forward to a little video when it's all painted and tarted up.

I'll do that Jason and thank you.

Jim the drawing is from a book by Henry Muncaster published in 1912, Model Stationary engines.

The book was reviewed by E.T. Westbury in a series of M.E. articles in 1957. I believe those articles are available online. Sorry I don't have a link but they are easy to google and find.

If you do decide to make this model, let me know. I have a spare cast iron cylinder casting which you can have for postage cost. The casting is from my own pattern. I had two cast in case I c**ked up one.

I am also doing a cad drawing which is upscaled so 1/16" = 2mm so the 5/8" bore is 20mm and the 1" stroke is 32mm etc etc.

Regards Geoff

Thanks for the info Geoff, I'll have a look for the drawing. If I decide to make it I'll drop you a message regarding the cylinder.

Jim

Julius de Waal has recently drawn up all of the engines in the Muncaster book in metric and most are larger, all from barstock construction. Should be on MEM.

Could you be tempted by my Muncaster?

Pretty little machine, Geoff.

Neil

I remember your Muncaster, Jason, but at the time I saw it I already had Stu Hart's Vertical Cross which was similar only with a different crosshead arrangement.

I've ordered the Muncaster book from Amazon so I'll have a better idea of whether the double acting oscillator (oscoscillator?) is a goer or not.

Jim

Jim, Julius' drawing is "Muncaster2.......................... in this post on MEM

Goodness me!!

Julius de waal has been very busy, his drawings are excellent.

His drawings show 24mm bore for the d/a oscillator so bigger than mine which is 20mm.

My engine has a cast iron meehanite type cylinder. I have lapped the bore to a fine finish with 1000 grade paste and oil. The piston is gun metal a little under (.050) 20mm diameter, so an easy fit. I was considering using a viton o ring say 17 bore x 1.5 dia section or 16 bore x 2mm section.

I have read that cast iron is not compatible with this type of ring.

I have some teflon coated yarn 1/8" square which could be another option

Any thoughts or opinions anyone

Geoff

Twin cylinder version driving paddle wheels in "Model Stationary and Marine Steam Engines"

Regards Ian.

I have used Vitron in quite a few cast iron cylinders both on the air/steam engines as well as the larger hit & miss IC engines and they seem to run fine with little drag and plenty of compression.

If you are just going to run it for display then it should also tick over slower with no ring fitted.

Thanks for the steer Jason. Unfortunately I don't get on with Julius' drawings, I find them cluttered and difficult to interpret.

Jim

I know what you mean!

Maybe a mix of the two when you get the book as it does not have full working drawings, mostly just general arrangements with some dimentions though that particular engine does have a bit more detail.

Well I've now received Muncaster's book "Model Stationary Engines" via Amazon.

As Jason pointed out the book doesn't contain a full drawing set, just the diagrams posted by Geoff at the top of this thread. I am now in a quandary: try and make the engine from the limited information in the book using bar stock, try and make the engine from the limited information in the book but to Geoff's metric conversion factor and using the cast cylinder he has kindly offerred me or try and make the engine at a larger size from Julius de Waal drawings using bar stock.

More coffee and cogitation required I think.

Geoff, I have sent you a PM

Jim

Hi All,

Well, it's all finished, painted, lacquered, etc. or as Jason would say "tarted up".

The base is an oak lap jointed frame with a briwax finish.

The baseplate is heavy, 150 x 100 x 10mm M.S. plate sprayed with a hycote primer and then lacquered to finish.

The frame, valve block, bearing blocks etc. are primed then two coats of halfords industrial grey enamel and again lacquered to finish.

The flywheel is hand painted with a humbrol primer and enamel.

Video of it running is on you tube, search Bobbie jones muncaster double acting oscillator. Seems to be running really well, good balance.

Hope it's of interest Geoff

Edited By JasonB on 31/07/2019 16:28:06

My version of the vertical cross; similar to Muncaster apart from cross head arrangement, from Stu Harts design...

George.

A very good looking engine, Geoff. Nicely finished and it runs well too. I am enthused to get my current project finished and set to on the casting for this engine you kindly sent me.

Jim

I have just googled Rogers revolving steam engine. Looks more than interesting

Roy

That turned out nicely Geoff, I've added the video to your post.